Male bees have an unusual desire to collect scents: they deposit scents from various sources in special pockets on their hind legs, thereby creating their own fragrance.
This has been observed since the 1960s. The reason for this has long been a source of speculation.
Researchers from Ruhr University Bochum, Germany, worked with colleagues from the University of California, Davis, and the University of Florida, Fort Lauderdale, to solve the mystery.
After three years of experiments in flight cages, the team discovered that bee fragrance acts as a sex attractant and increases male reproductive success.
Mating Activities Difficult To Observe
The research team, led by Ph.D. student Jonas Henske and Dr. Thomas Eltz from the Bochum Department of Animal Ecology, Evolution, and Biodiversity, published their findings in the journal Current Biology on April 12, which was published online, as per Phys.org.
There has been much speculation about the fragrance’s purpose: some have suggested that it could be an attractant or a wedding gift for females, or that the scent is used to communicate with rivals.
The group led by Thomas Eltz had previously demonstrated that male bees transport fragrance out of pockets on their hind legs during the courtship ritual.
“What we didn’t know, however, was who was supposed to receive this signal,” Eltz explained. “The females? Or the rival males?”
The mating of orchid bees is extremely rare in the wild, and even in experiments, as Thomas Eltz describes the challenge, it has been nearly impossible to get them to mate.
This is why the Bochum-based researchers and their US colleagues tried to provide the bees with optimal conditions, such as a specially large cage and the perfect pollen plants.
The researchers began the experiment by luring male bees to artificial scent sources, which the bees then used to create a fragrance.
The fragrance was extracted from the pockets on the hind legs using a microcapillary and then transferred to one of the bees used in the experiment.
In this case, two males kept under identical conditions competed for the attention of females.
Courtship Behavior That Is Typical With Varying Degrees Of Success
The males, whether scented or not, displayed typical courtship behavior.
Mating took place with 27 females, each of whom mated with a single mate, as per ScienceDaily.
In 26 of these cases, male bees equipped with fragrance were involved.
In one case, a male from the control group reproduced, which should have been fragrance-free; however, the researchers discovered hints that this individual had also acquired a scented mixture-fragrance theft does occur on occasion.
Jonas Henske performed paternity tests to prove beyond a shadow of a doubt which males had mated.
He compared the brood’s genetic make-up to that of male bees.
According to Thomas Eltz, the fragrance is an attractant for females and triggers mating behavior in them.
Their findings also showed that fragrance is not used as a status symbol among males. When a male was in possession of fragrance, he was no more likely to defend his courtship site.
Importance Of Orchid Bees
Orchid bees are significant for a number of reasons. For starters, they pollinate many plant species, particularly orchids, which have evolved to attract and reward them with specific scents.
Some orchids are entirely dependent on orchid bees for reproduction.
Second, because they are sensitive to human disturbance and habitat loss, they are indicators of the health and diversity of tropical forests, as per Ask a Biologist.
Third, they are fascinating examples of coevolution and sexual selection, having evolved complex behaviors and structures for collecting and displaying scents in order to attract mates.
Orchid bees are also visually appealing and colorful; some may value them for their aesthetic value.
Source: Male Bees Have Incredible Passion for Collecting Scents, Creating Own Fragrances | Nature World News
